Hydroelectric gearshift



Dec. 19, 1950 L. T. woMAcK ETAL HYDROELECTRIC GEAR SHIFT 6 Sheets-Sheet 1 Filed Dec. 16. 1947 s. ma mmk M M W N VEN TORS W m, M

L. T. woMAcK ETAL HYDROELECTRIC GEAR SHIFT Dec. 19, 1950 Filed De. 16, 1947 6 Sheets-Sheet 2 Dec. 19, 1950 L. .1'. woMAcK ETAL HYDRoELEcTRIc GEAR SHIFT Filed nec. 1e, v1947 IN VEN TORS L [0N/@R0 7.' WOMA CK Dec. 19, 1950 L.1'..woMAck ETAL HYDRoELEcTRIc GEAR SHIFT s sheets-sheet 4 Filed Dec. 16, 1947 l?. I. w

INVENTORS t0/IMD 7,' Www/)CK A/v BY JEWELLJ :vo/MACK Q @1M QL, L@ ,n f 4 a 3% @l Dec. 19, 1950 l.. T. woMAcK Erm.

HYDROELECTRIC GEAR SHIFT Filed Dec, 16, 194'? 6 Sheets-Sheet 5 Fi gr. I3

INVENTORS fo/WIRD Won/MCA BY A/vo ffweu .z Womack 47' T UIP/VE l/J Dec. 19, 1950 L.. T. woMAcK ET AL 2,534,493

HYDROELECTRIC GEAR SHIFT Filed Dec. 16, 1947 6 Sheets-Sheet 6 ffm-'I BYJEWEA 41]. WMC/f Patented Dec. 19, 1.95()

UNITED STATES PATENT OFFICE HYDROELECTRIC GEARSHIFT Leonard T. Womack and Jewel Jackson Womack, Carpinteria, Calif.

Application December 16, 1947, Serial No. 791,968

14 Claims.

Our invention relates to electrically-controlled, hydraulically-actuated, gear-shifting devices for variable speed transmissions. The device according to the invention relates more speciiically to such gear-shifting devices as are applicable to the transmissions of motor vehicles, particularly motorcycles, but is readily applicable to any variable speed transmission.

With the foregoing in view, an object of our invention is to provide an improved hydro-electric clutch and gear-shifting mechanism for a variable speed transmission.

A further object is to provide an improved hydro-electric clutch and gear-shifting mechanism for a variable speed transmission wherein a selector taps a source of electric power which is then operative to actuate hydraulic clutchengaging mechanism, and is thereafter operative to actuate a hydraulic gear-shift mechanism, and which thereafter automatically re-engages the clutch, power for said hydraulic mechanism being supplied by a pump driven by the engine of the motor vehicle or, alternatively, when such engine is not running, from either a source of hydraulic iiuid under pressure or from a manually-actuated pump.

A further object is to provide an improved hydro-electric clutch and gear-shifting mechanism which includes a novel hydro-electric mechanism for disengaging and engaging a clutch for a transmission.

A further object is to provide an improved hydro-electric clutch and gear-shifting mechanism for a variable speed transmission which includes a novel hydro-electric mechanism for actuating gear-shifting mechanism for a transmission.

A further object is to provide an improved hydro-electric clutch and gear-shifting mechanism for a variable speed transmission which includes a novel closed hydraulic circuit, pump means for circulating fluid therein, and a source of hydraulic uid under pressure.

A further object is to provide in a device such as that last described a novel hydro-electric clutch and gear-shifting actuating mechanism.

Other objects and advantages reside in the particular structure of the invention, combination and arrangement of the several parts thereof7 and in the particular method or mode of operation, all of which will be readily apparent to those skilled in the art upon reference to the attached drawings in connection with the following specification, wherein the invention is shown, described and claimed.

In the drawings:

Figure 1 is a longitudinal vertical section through a preferred form of a hydro-electric servo mechanism for actuating a gear-shifting means;

Figure 2 is a view like Figure l through a preferred form of hydro-electric, clutch-actuating servo unit;

Figure 3 is a horizontal section taken substantially on the planes of the lines 3-3 of Figure 2;

Figure 4 is an elevation of a motorcycle showing the arrangement of the several parts of the invention relative thereto:

Figure 5 is a longitudinal vertical section through a detail of the invention;

Figure 6 is a transverse vertical section taken substantially on the plane of the line 6-6 of Figure 5;

Figure 7 is a longitudinal horizontal section taken substantially on the planes of the lines 1 1 of Figure l, certain parts being omitted;

Figure 8 is a transverse vertical section taken substantially on the plane of the line 8 5 of Figure 7;

Figure 9 is a transverse vertical section taken substantially on the plane of the line 9 9 of Figure '7;

Figure 10 is a diagrammatic view of the electric circuit utilized in the invention;

Figure 11 is a longitudinal vertical section through a combined hydraulic fluid storage tank and hydraulic fluid pressure tank according to the invention;

Figure 12 is a longitudinal vertical section through a pump for the hydraulic fluid according to the invention;

Figure 13 is a horizontal section taken substantially on the plane of the line I3-I3 of Figure 12;

Figure 14 is an end elevation of a detail of the pump of Figures 12 and 13;

Figure 15 is an end elevation with parts being broken away and parts shown in transverse vertical section of a detail of the hydro-electric unit shown in Figure 1;

Figure 16 is an exploded view showing a plurality of contacts utilized in the hydro-electri unit of Figure 15;

Figure 17 is a fragmentary longitudinal vertical section taken substantially on the line ll-I'l of Figure 15, parts being omitted;

Figure 1S is a fragmentary elevation of a detail with parts being shown in longitudinal Vertical section and taken substantially on the planes of the line l8-I8 of Figure 2;

Figure 19 is a transverse vertical section taken substantially on the plane of the line IQ-IQ of Figure 3;

Figure 20 is a transverse vertical section taken substantially on the plane of the line Z-Z of Figure 3;

Figure 21 is a schematic View showing the hydraulic system according to the invention, apart from the motor vehicle.

Figure 22 is a diagrammatic sectional View showing the transmission gears and clutch.

The invention disclosed specifically hereinafter includes an electrical system which is diagrammatically illustrated in Figure 10, and which is powered by a motor vehicle battery. Such elece trioal system comprises a plurality of electric circuits, some of which are shown diagrammatically in Figure 10, and which circuits are operatively associated with a hydraulic circuit, Figure 21. The hydraulic circuit includes a pump, Figures l2 and 1S, which is driven either by hand or by the motor of a motor vehicle. Also included in the hydraulic circuit is a storage tank, Figure 1l, for spent hydraulic fluid, an accumulator tank, Figure 11, for storing hydraulic fluid under pressure, and means for operating the clutch and the gear-shifting mechanism. Such last-named means comprises a hydraulically-powered, electrically-controlled clutch servo, Figures 2, 3, 19 and 20, for engaging and disengaging the clutch, and a hydraulically-powered, electrically-controlled gear-shifting servo, Figures 1, '7, 8, and 9, for performing gear-shifting acts. The operation of the invention, briefly, comprises initial actuation of a selector means, which is effective to close a selected circuit to the clutch servo to actuate the same to disengage the clutch. Thereafter, upon completion of the disengagement of the clutch, the selected circuit is completed to the gear-shifting servo, whereby to actuate the same to perform a selected gear-shifting act. At the completion of the selected gear-shifting act, the clutch servo is again actuated to engage the clutch.

Referring now to Figure 4, 24 designates generally and diagrammatically a motorcycle having a pair of handle bars 2t which may include a brake lever 25 for actuating brakes, not shown. The motorcycle includes a frame 2l of any suitable form on which is mounted the usual engine 23 which is operatively connected to a clutch and transmission housing 29. A bell crank 28 is pivoted in the housing 2Q for shifting the gears contained therein, and a clutch pedal 22 is also operatively connected to the housing 29 for engag ing and disengaging the clutch in the usual manner. The gears in the housing -29 are of any suitable or usual form for motorcycles, and itis to be understood that shifting of the gears to vary the speed ratio is accomplished by moving the bell crank 28 in either a clockwise or a counter-clockwise direction in the usual manner. It is to be understood that while we have disclosed a device according to our invention as applied to a motorcycle, the device is equally applicable to the shifting of gears in other` devices and/or motor vehicles wherein the shifting is accomplished by straight-line movement of -a single actuating member.

Thus, Figure Z2 illustrates by way of an example and in diagrammatic form, a clutch and transmission suitable for use with our device. As there illustrated, the engine 23 is provided with a drive shaft 235 extending into the housing 2Q. The shaft 235 has splined thereon a driving clutch element 236 provided with a collar 231 adapted to be engaged by a fork 23S for moving the driving clutch element into and out of engagement with a driven clutch element 239 fixed to a shaft 235. The fork 238 is operatively connected to a clutch servo piston rod 29 the operation of which will be described more fully hereinafter. A triple gear Zi is splined on the shaft 235 inwardly of the housing 2Q and is shiftable therealong by a fork 2M engaging a collar 2&12. The fork 2li! is operatively connected to the shaft of the bell-crank ES whereby to shift the gear 240 upon rocking of the bell=crank Z8 in a well known manner. A pair of counter-shafts 2513 and 2M are disposed in the housing in spaced parallel relation to the shaft 235. The counter-shaft 2&3 comprises a take-off shaft and has a free end extending outwardly of the housing 29. Such free end 1s connected by bevel gears 265, stub shaft ZGS and sprocket 2? to the chain drive for the rear wheel of the motorcycle. The counter-shaft Ztl-i has fixed thereon a spur gear 248 which is in mesh with a spur vgear portion of a double spur gear 249 freely rotatable on the shaft 235. The portion 25E is ofthe same ratio as the spur gear fii whereby no speed change is accomplished. Likewise, the counter-shaft 263 .has fixed thereon a spur gear 2122 of the same size as the Vother gear portion'@ of the double gear 249. Thus, motion may be transmitted from the counter-shaft 2li-fi to the take-off shaft 2&3 without any speed change. A reverse gear 253 is fixed to the countershaft 2G13 and is in constant mesh with a reverse idler 25d which in turn is mashed with a spur gear 255 freely rotatable on the shaft 235. The gear 255 is provided with axially directed teeth 56 adapted to mesh with complementary teeth 25? formed on the end surface of the gear portion 258 of the triple gear 24). with the parts in the position shown, the device is in neutral but if the triple gear 249 is moved to the right, the same will be engaged with the gear 255 whereby to drive the sprocket 24'! in a direction the reverse of the normal travel of the motorcycle. The counter-shaft 2de is also provided with a spur gear 25@ adapted to mesh with the gear portion 25S of the triple gear when the same is moved to the left of the position shown in Figure 22. The gear 25d comprises a low gear. Further movement of the triple gear Zi to the left causes a central and larger gear portion 25S to mesh with a second gear 2t! fixed on the countershaft 245. Still further movement of the triple gear 2te to the left causes the other end gear portion 262 to be meshed with a third gear 23 fixed on the counter or take-off shaft 2&3. Still further movement of the triple gear 24e to the left causes the end teeth of the gear portion 252 to mesh with complementary teeth 2&5 formed on the abutting surface of a spur gear ll freely rotatable on the shaft 235. The gear 2li? is in constant mesh with a high gear 2li xed on the take-off shaft 243. Thus, with the clutch members 236 and 239 engaged, the triple gear Zeil rotates constantly with the shaft 235 moreover, it is obvious that by moving the triple gear 2Q@ from right to left along the driven shaft l235, the device is successively operated in reverse, neutral, rst, second, third and high gears.

Referring now to Figure 10, the electric system, which is disclosed diagrammatically there, is powered by the usual motor vehicle battery 3S which is grounded, as usual, at 3l. While the system is diagrammatically shown in Figure 10,

, elements of the system are disclosed in Figures 1, 2, 3, '1, 8, 9, 15, 16 and 17, and will be referred to more speciiically hereinafter. Also, for the sake of simplicity, the diagram of Figure has been restricted to the particular leads and circuits incident to the invention, and all other circuits, such as the ignition circuit for the motor vehicle and the light circuit, have been eliminated. A lead 32 from the battery 39 extends to a selector unit 33 which is preferably mounted on one of the handle bars 23 of the motor vehicle by any suitable means. The selector unit 33 includes a plurality of selectorswitches 28, 34, 35, 35, 31 and 38 of any suitable character. Such switches respectively close circuits to leads 29, 42, 43, 44, 45 and 46 extending therefrom. The selector switches aforesaid may be of any suitable form and comprise no part of the present invention. Interposed between the selector unit 33 and the battery 39 are a pair of branch leads 49 and 4l, the purpose oi which will be described later. Ob viously, the number of selector switches and leads will vary in accordance with the number of speed changes in a given transmission.

Referring now to Figure 1 in conjunction with Figure 19, the ends of each of the leads 29 and d2 to 48, inclusive, are connected to individual binding posts i8 of a junction box 41. For the purpose of simplicity, in Figure 1, only the leads d4 and 43 have been shown connected to binding posts. Each of the binding posts 48 is connected to a connector 49 which is embedded in an outer end wall 52 of the junction box 41. The junction box 41 is substantially hollow and cylindrical in form, and comprises outer end walls 52 and 58, inner end walls 53 and 54 which are slightly smaller in diameter than the outer end walls and which are surrounded by a cylindrical side wall 59. The side wall 59 surrounds the peripheries of the inner end walls and the free end edges of such side wall seat against the inner surface of the outer end walls 52 and 55. All of the end walls and the side wall are preferably connected together to comprise a unit by any suitable means, not shown. Also, the outer and inner end walls, as well as the side wall, are preferably made of insulating material of any suitable character.

Each connector A9 is operatively connected to one of a plurality of slide rods 59 which are formed of current-conducting material and which extend axially of the junction box 41 in concentric relation to the axis thereof. Such rods 58 extend through the inner end walls 53 and 54 and are seated in the outer end wall 56. Each of the inner end wall 54 and outer end wall 58 is provided with aligned, axially-disposed apertures 55 and 51 therethrough for a purpose to be described later. In brief, however, such aligned apertures 55 and 51 permit the free passage therethrough of a piston rod extension 58, the free end of which is connected in any suitable manner, as by the screw 8i, to a disc-like slider 58.

rlhe slider 3@ is preferably made of insulating material and is provided with an annular series of spaced apertures to slidably receive the slide rods 59, whereby the slider 63 is freely slidable thereon. Referring specifically to Figure 15, the slider is provided with a plurality of radiallyextending passages 32, the inner ends of which at least partially expose outer surfaces of the slide rods 58. A brush 63 is radially slidable in each of the passages 82 and is loaded for radial outward movement by any suitable spring means 35. The inner end of each spring B5 is formed with a shoe 64 of any suitable form which slidably engages the exposed surface of the slide rod 50.

The outer end of each brush 63 slidably engages' a stationary contact generally indicated at and which is counter-sunk in the inner surface of the cylindrical outer wall 59 of the junction box. There is a separate stationary contact 6E for each brush 63, and each of such stationary contacts is insulated from the other. Each of the stationary contacts 36 comprises a section B1 of current-conducting material and a section 269 which is likewise of current-conducting material, and which sections are separated by a block 68 of insulating material. The block 68 is of such a length that a brush 93 may be seated thereon without being in contact with either of the sections 81 or 289, whereby to break a circuit previously established through the brush 63, for a purpose to be described later. As is apparent from Figure 16, wherein all of the stationary contacts 63 are displayed in exploded relation, each of the sections 269 and 61 is of a different length. Also, such insulating blocks 68 are staggered, whereby when assembled in the cylindrical wall 59, the insulating blocks describe a spiral, or helix. Opposite ends of the stationary contacts 6E are connected by connector rings 89 and 10 which are embedded respectively in the inner walls 53 and 54 of the junction box.

The connector ring 39 is connected by a lead 1l to a relay 12 in such a manner that the current owing in the lead 1! actuates the coil 14 of the relay to attract the armature 13 thereof, whereby such current will thereafter flow through the armature 13 to a further lead 15, see Figures 1 and 10. The relay 12 is a one way relay in that the coil 14 will be energized only when current news thereto through lead 1l. However, with the coil 14 deenergized whereby armature 13 is in the open positionof Figure 10, the relay will not be actuated by current flowing in lead 15 or lead |33, to be described later. The lead 15 is operatively connected to a further lead 16 which is connected to one pole of a clutch servo solenoid 11, the opposite pole of which is grounded, as at 18. As will appear later, the clutch servo solenoid 11 is effective to control the engagement and disengagement of the clutch. The opposite connector ring 19 is connected, as by a lead 19, to a second one way relay 89 which is similar to the relay 12 whereby the passage of current through the lead 19 not only actuates the relay, but also transmits current through the armature 8l thereof to the lead 13 aforesaid. However, with armature 8l open, the relay cannot be actuated by current flowing in leads 13, 15 or |93 all of which are connected together, Figure 10.

The connector ring 69 of the junction box is also connected by a lead 82 to one end oi the coil of a solenoid 83 of a gear-shifting servo to be described later. The other end of the coil of the solenoid 83 is connected by a branch lead 84 to a main lead 85 which in turn is connected to a stationary contact 86 of a switch 89. A second stationary contact 31 of the switch is grounded in any suitable manner, as at 88. The switch 89 also includes a pair of spaced contacts 90 and 9| which are normally bridged by a movable contact 92. A spring 93 loads the movable contact 92 for bridging the stationary contacts 93 and 9|. A branch lead 95 connects the stationary contact 9i to the ground 88. The movable contact 92 has an actuating arm 94 which extends outwardly of the housing for the switch 89 for a purpose to be described later. The stationary contact 99 is connected by a lead 93 to av suitable signal 91, the opposite pole of which is connected by the branch 'lead '4B to the battery 33. Thus, in the normal position of the switch 8S, the movable contact 92 bridges the stationary contacts 9,@ and 9| to close a circuit to the signal 9i. It follows, then, that in the normal position of the switch 89, the circuit to the signal Si? 'is closed and the signal is actuated, and that when the movable contact 92 is moved to open such circuit and to bridge the stationary contacts 86 and 8l, the circuit to the signal lll will be broken. As is indicated in broken lines, Figure l0, the actuating arm ed for the movable contact 92 is adapted to be engaged by the free end 98 of a clutch servo piston rod 99 and moved so that the movable contact 92 is extended across the stationary contacts 86 and 8l to bridge the same against the action of the spring 93. When this occurs, the circuit to the solenoid 83 will be grounded and the solenoid will, therefore, be energized. In like manner, the opposite connector ring l@ of the junction box is connected by a lead Iil to one terminal of the coil of a solenoid IUI of the gear-shifting servo to be described later. The opposite endof the coil of the solenoid lill is connected by lead |92 to the lead 85 to the stationary contact 8S of the switch 89.

In the operation of the device as so far described, it will be apparent that upon the actuation of a selector button, say the button 35, current will ow through the lead i3 binding post 58 to the connector ce, thence to a slide rod 50, thence through an appropriate contact 64, spring G and brush G3 of the slider 5E) to one of the stationary contacts 65. From there the current will flow to the connector ring S9 or the connector ring depending upon which side of the insulating gap 58 the brush 63 happens to be located. Current will then flow through one of the leads 'H or 'i9 to one .of the relays 'S2 or il. From there current will iiow through the lead 76 to the clutch servo solenoid 'il' to actuate the same. At the same time,.current will iiow from one of the connector rings 8S or 'lil through one of the leads 82 or .Idil through one of the gear-shifting servo solenoids 8S or lill, lead 85 to the stationary contact 8E of the switch 8S. However, the gearshifting servo solenoids will not be energized because the switch 8S remains open until the clutch servo pison rod 99 has advanced to the leftehand position, Figure l0, at which point the movable contact has bridged the stationary contacts 8S and 8l to complete a circuit to the gear-shifting servos. Thereafter, by means to be described later, the gear-shifting servo will be effective to perform a selected gear-shifting act at the conclusion of which the slider Se and its appropriate brush' will be centrally positioned on an insulating gap E8 for the particular gear-shifting act and will, therefore, break the circuit to both the clutch servo-solenoid and to the appropriate gear-shifting servo solenoid. When this occurs, as will appear later, the clutch servo-solenoid 11 is deenergized, whereby the clutch servo piston rod 99 is retracted to re-engage the clutch. Obviously, this action also permits the spring 93 to return the Imovable Contact 32 Vof the switch 89 to a position to bridge the stationary contacts 90 and Si and re-energize the signal 91.

ihe other gem-shifting operations are performed in the saine manner by actuating a diierent selector button, and inasmuch as current will then iiow in the saine manner to a brush S3 which is not located upon an insulating gap Gif, a further gearnshifting act will be performed in thesame manner. A lead H33 is connected to .thelead V'iii lconnecting the relays lil and :60, yand d such 'lead :63 is connected 'to one pole of a toggie switch itil, the other pole of which is connected by a lead il to the lead 32 of the battery 3D. rhus, the toggle switch ld is in a direct circuit iroin the battery 3% to the clutch servo solenoid?? hy wayoi the leads 433, rland l. Consequently, when the toggle switch mi is closed, the ,clutch servo solenoid Ti will be energized irrespective of the rest of the circuits. This arrangement permits the driver of the vehicle to leave the vehicle in a selected gear when he stops by merelyfclosing the toggle switch IEM. This operation will disengage the clutch by energizing the clutch servo solenoid il. Likewise, when the operator wishes to .start up in the Isame gear, he merely opens the toggle switch i913 which permits the clutch to engage by deen-ergizng the solenoid 'it'. lThe signal di is actuated at all times when the clutch is engaged, and, therefore, serves as tell-tale.

Referring now to Figures 2 and 3, and to some extent to Figures i8, i9 and 2U, the clutch servo will now be described. Such clutch servo comp any suitable housing 35 which is prefera" y of streamline conguration, if mounted on the exterior of the vehicle, such as a motorcycle, a l such hou-sing has secured therein by any uitable means a hydraulic valve chest i, a Aydrai ic cylinder SG?, which includes a hyi ["c piston i513 fixed on the inner end of the hitch servo pis-ton rod $9 aforesaid. Hydraulic uit s plied to the valve chest E06 by means f an intake conduit E535? and spent hydraulic `Vluid is discharged from the valve chest by means i the exhaust conduit l iii. A double-action slide aive i l is slidable in the valve chest and is connected any suitable means H2 to the outer end of the armature H3 of the clutch servo solenoid An expansive spring lili is operatively engageable with armature l i8 in any suitable manner to load the saine in its normal position when the solenoid 'il is (ie-energized. The slide valve lil is slidable in a passageway l which may be vented at one end, as at E28. The slide valve iii is provided with longitudinally-spaced pairs oi inlet ports H5 and H3, and with longi tudinaily/spaced exhaust ports H6 and iii. The intake conduit m9 is provided with a pair or branch intake conduits l lil and l2@ which lead respectively by way of the intake ports H5 and il@ ci the slide valve to opposite ends of the cylinder i'i by way of conduits li and E25. Such conduits iid and lie are combined intake and exhaust conduits. The exhaust conduit I l) likeis provided with branch exhaust conduits li i2?. which open respectively into the two-way conduits lili and 25 aforesaid through exhaust ports il@ and H7 of valve il l. The arrange nt of the ports H5, H5, lli and H8 is as i ual with double-action slide valves in that an intake port is open for one end of the an exhaust port for the opposite end is open, and vice versa.

A branch conduit i2@ opens off the main intake conduit E and leads to any suitable pressure gauge l-E `for indicating the pressure in the intake line. Each of the branch inlet conduits liti and 52E is provided with a suitable valve control `ii and 132, respectively, whereby a flow of fluid in either or both of such branch inlet conduits may be controlled for controlling the speed of operation oi" the piston m3, and, consequently, the speed by which the clutch is engaged or disengaged. IThe housing l for the clutch servo is provided with a suitable aperture 133 for the C) SL extension of the piston rod 9S therethrough, and a further aperture |34 may be provided for access to the speed control means |32. Likewise, a further aperture I 35 is preferably provided to permit viewing of the pressing gauge |30. It is to be understood, further, that the housing is composed of one or more parts, whereby the same may be taken apart to permit access to the various portions of the servo.

Referring specifically to Figure 2, the operation of this portion of the invention will be apparent. In Figure 2, the clutch servo-solenoid 1'I is deenergized, whereby the spring ||4 has assisted the general de-energizing movement of the armature ||3 to move the 4slide valve to a position where hydraulic fluid under pressure enters the valve chest |46 through the intake conduit |09, passes through the branch intake conduit I I9, through the intake port ||5 of the slide valve, and into the two-way conduit |24 for the lefthand end of the cylinder |01. With the valve in such position, it is obvious that the piston |08 will be driven to the right-hand end of the cylinder |01 and that exhaust or spent hydraulic fluid will be discharged from the cylinder by way of the two-way conduit |25, valve lport ||'I, the branch exhaust conduit |22 and the main exhaust conduit IH). Likewise, when the solenoid 'I1 is energized, the armature ||3 will be retracted to the left against the action of the spring II4, whereby the slide valve I I is reversed to position the exhaust port H5 across the exhaust conduit branch |24 and simultaneously position the inlet port I I8 across the branch inlet conduit |25. This arrangement permits hydraulic fluid under pressure to flow through the two-way conduit |25 to the right-hand end of the cylinder |01, whereby to drive the piston |03 to the left-hand end of the cylinder. This action extends the piston rod 99 to a position where, at the end of its stroke, it engages the member 94 of the movable contact $22 of the switch 89, Figure 10, to move the same to a position to bridge the stationary contacts 85 and 31 and thereby energize the gear-shifting servo solenoids 33 or IQI. In like manner, upon de-energization of the clutch servo solenoid 11, the armature ||3 returns to the position shown in Figure 2, whereby the free end 98 of the piston 99 is retracted out of engagement with the movable contact actuating member 52 which permits the spring 523 to return the movable contact across the stationary contacts 9U and 9| and break the circuit to the servo solenoids 83 or IS The gear-shifting servo, according to the invention, is basically disclosed in Figure l, and supplemental views thereof are found in Figures 7, 8 and 9, while related parts to be described later are shown in Figures 5 and 6. Referring speciiically to Figure 1, as well as Figures '1, 8 and 9, the gear-shifting servo comprises a housing |45 of any suitable form, but which is preferably streamlined, as shown, when used exteriorly on a motorcycle. The housing |45 has mounted therein in any suitable manner a valve chest |4| to which is attached a hydraulic cylinder |42 in which is slidably mounted a piston |43. The piston |43 has a piston rod 53 extending axially outwardly of the cylinder and to the free end of which is attached the slider Eil of the junction box 41, as previously described. The piston |43 also provided with a second piston rod |44 which extends axially of the cylinder in an opposite direction to that of the piston rod 58. The second piston rod |44 also extends outwardly of the housing |40 and is operatively connected to gear-shifting means to be described later. Hydraulic uid under pressure is supplied to the valve chest I4| by a main intake conduit |45 which is provided with a branch conduit |41 leading to the lefthand end of the cylinder |42, and a second branch conduit |49 leading to the right-hand end of the cylinder. Spent hydraulic fluid is discharged from the valve chest by the main exhaust conduit |46 into which opens the branch exhaust conduits |48 and |54. The branch inlet conduit |41 and the branch exhaust conduit |55 merge adjacent the left-hand end of the cylinder into a two-way conduit |52. ln like manner, the branch inlet conduit |49 and the branch exhaust conduit |43 merge adjacent the right-hand end of the cylinder into a two-Way conduit |5|.

The valve chest |4| has mounted therein in a slideway |54 a single-action slide valve |53. The slideway |54 extends across the branch inlet passage |41 and the branch exhaust passage |48. The slide valve |53 is provided with an inlet port |55 and an exhaust port |53. One end of the slide valve |53 is connected in any suitable manner, not shown, to the free end of the armature |51 of the left-hand gear-shifting solenoid 83. When the solenoid 83 is de-energized, the slide valve |53 is so positioned that neither the branch inletconduit |41 nor the branch exhaust conduit |48 is open. Thus, when the circuit to the solenoid 83 is open, the ports |55 and |53 are closed. The opposite end of the valve chest |4| is likewise `provided with a slideway |59 in which is slidable a single-action slide valve |58. The slide valve |58 is provided with an intake port |5| andan exhaust port |65 which are registerable respectively with the branch inlet conduit |49 and the branch exhaust conduit |55. One end of the slide valve |58 is detachably connected by any suitable means, not shown, to the armature |62 of the second gear shift servo solenoid |0|. As is the case of the first slide valve |53, when the solenoid Illl is de-energized, the normal position of the armature |52 positions the slide valve |58 so that both the branch inlet conduit |49 and the branch exhaust conduit |55 are closed. Thus, with both solenoids |33 and I|i| de-energized, no fluid will flow in either direction through the valve chest and the piston |43 will remain in a balanced state at whatever point it had reached at the time of closing either the valve |53 or the valve |53. Both of the slideways 54 and |59 are preferably in axial alignment, and the adjacent ends thereof are preferably Vented by any suitable vent 4t2. The inlet conduit |45 is provided with an adjustable valve member |53 which may comprise a threaded valve, whereby the flow of fluid to the branch conduits |49 and |41 may be controlled to regulate the speed of operation of the piston |43 and, consequently, the speed of the gear-shifting act. The housing |45 is formed with a suitable opening |64 therethrough to permit access to and actuation of the valve |53 and additional openings such as |55 and |55 may be provided for the passage of the piston rod |44 and the entrance of the leads |42 to |45, inclusive. Obviously, additional openings through the housing |45 may be formed or furnished as required. In like manner, the housing I 43 is preferably made of several parts so that it may be opened to permit access to the servo parts contained therein.

The right-hand piston rod |44 for the piston |43 may comprise a plurality of articulated sections suitably connected together, as by a pivot |51 and a turnbuckle |58, Figure 1, and a ter- 1.1 minal portion. |69 of such piston rod is suitably connected in any suitable manner to a damping device generally indicated. at |19', Figures 5 and 6. The purpose ofthe damping unit |19 is to provide a cushioned connection between the piston rod terminal end |99 and the bell crank lever 28 which accomplishes the actual shifting of the gears.Y The arrangement tobe described isV ef'- fective to prevent clashing and chipping of the gears when gears' to be shifted are not in exact alignment. In effect, the device permits the gear-shifting servo to feel for the proper alignment as it' shifts the gears.

The damping unit' |19 comprisesl an outer cylinder |1| which is hollow and which has its ends closed by any suitable end caps |12. The end caps |12 are axially apertured, as at |13, for the free passage therethrough of the free end |69 of the gear shifting servo piston |44. Such free end is formed with a transverse vertical bore |14' on a portion normally positioned centrally of the cylinder |1|. Such bore |14 has seated therein a cross-pin |15, the free ends of which extend outwardly of the end |69 and slidably abut the inner periphery of the' cylinder The free end |99 isf also formed withA a pair of o'ppcsitely-disposed' transverse recesses |16 at right angles to the bore |14 and on planes interseatingV the same'. Each recess |19 seats the inner end' of one of a pair of cross-pins |11, the outer ends of which also extend outwardly of the free end |99 and slidably abut the inner periphery of cylinder |1|'. A-n inner cylinder |19 concentrically surrounds the free end |69 and is formed with four radially-spaced and elongated pin slots |19, there being a slot |19' for the outer ends of each pin |15 and |11. A pair of coil springs |89 are concentrically disposed about opposite ends of the inner cylinder |18 with the inner free ends of the springs abutting opposite` sides of the pins |15 and |11. Washers |81 are concentrically-disposed about the inner cylinder |18 and may be interposed between the outerends of the springs |89 and the inner periprheries of the end caps |12.- A bell crank pin |82 extends radially of thel outer cylinder- |1 and is xed thereto. The bell crank pin |82 isv pivotally connected to the free end of the bell crank 29, whereby to actuate the same in either direction upon reciprocation of the piston |94 and the free end |69 thereof.

It follows from the foregoing that upon reciprccation of the gear shift servo piston |44, the free end |99 thereof will reciprocate the damping unit |19, whereby to actuate the bell crank lever 23 in either direction. At the same time, upon actuation of the bell crank lever 28' and in the event that the gears are not properly aligned, such gearsV will resist meshing. Obviously, however,- when thisv occurs, one of the springs |39 of the damping unit will yield to permit continued extension of the piston rod |49 and free end |59 thereof. At the same time, when the gears to be meshed do become aligned, thel load of the spring |89 which has been compressed by this lost-motion action will suflice to mesh the gears without clashing of the same. The same action occurs irrespectivev of which direction the piston IM is r'eciprocated to perform a gearshifting act.

The gear-'shifting' servo and the clutch servo are operated by hydraulic fluid' under pressure from a` closed hydraulic circuit which is diagrammatically illustrated in- Figure 21'. Thus, the intake conduits |99 and |45 for the clutch servo and the gear-shifting servo, respectively, are fed byY a pressure conduit |33 which in turn is fed by a pressure conduit |94 leading from the output side of a pump |85, to be described later. The intake conduits |99, |95, |83 and are connected also by a conduit |35 to a source of hydraulic fluid under pressure |31. Such source |51, hereinafter called an accumulator, to be described later, comprises broadly a tank including means for retaining hydraulic fluid therein under pressure. Thus, the hydraulic line or conduit |36 is effective to supply hydraulic fluid under pressure to the servos when the pump is not operating. When the pump is operating, thev conduit |95 serves merely to maintain pressure in the accumulator |81. The exhaust conduits It!) and |45 for the servos mergeA intoV a single conduit |89 which in turn empties into a storage tank |89, to be described later. The" storage tank |99- is combined' with the accumulator |31 in a unitary structure. A supply conduit |99 delivers hydraulic fluid from the tank |89 to" the intake'side of the pump |85 to complete the closed hydraulic circuit.

Referring now to Figures l2, i3 and 14, the pump |95, according to the invention, is a gear pump and comprises a housing 19|, which encloses a pump block |92, which is secured in any suitableI manner to an appropriate part of the framev 21 of the motorcycle. In practice, we have found it desirable to mount the pump on the valve gear plate of the motorcycle. The pump block |92 has journaled therein a drive gear |93, which operates in a cylinder 29s in the block and which includes a drive shaft |94.. The drive shaft |99 has a splined connection 292 with a clutch shaft |99 having driven clutch teeth |91 of the ratchet type formed on its free end. A driving clutch having complementary ratchet teeth |93 normally engages the driven clutch teeth |91, whereby to rotate the shaft |94 in the direction of the arrow, Figure l2. The driving clutch |99 is connected to the motorcycle'engine in any suitable manner, not shown.

e The spline connection |92 is loaded by a spring |95` which is interposed in a pair of telescoping recesses formed on the abutting ends of the shafts |94 and |95. Thus, the spring |955 loads the ratchet teeth |91 to maintain the same normally engaged with the driving ratchet teeth |93. However, it is obvious that the spring |515 will permit yielding of the clutch shaft |95 if reverse rotation of the parts are attempted, whereby the teeth |91 and |98 will ride over each other in a Well known manner. This feature protects the gear pump from damage in the event of back-firing of the motorcycle engine. The opposite side of the driving gear |93 is formed to provide an axial socket 29@ of any suitable form which is adapted to be engaged by a crank, not shown, of any suitable type to permit hand operation of the pump when, for any reason, it is necessary to actuate the pump by hand. The crank is applied to the socket 299 through an opening 29| formed in the housing |9| in alignment with the driving gear |93. The driving gear |99 is in mesh with a usual idler gear 293 which is also operative in the cylinder 299.

The pump blocky |92 is provided with a conduit 295 in open communication with the supply conduit |99 from the tank |89. Such conduit or passage 295 in turn opens into a feed passage 206 which leads to a cylinder 294 in which the gears operate. The gears |93 and 293 operate provide a non-return valve.

in the usual manner of gear pumps and deliver fluid under pressure to the output passage 201 leading from the cylinder 2524. The pressure line 184 is in communication with the output passage 201 by way of a ball valve 208 loaded by a spring 209 to comprise a non-return valve. The output passage 201 is also in communication with a relief passage 21d by way of a ball check valve 210, which is spring loaded, as at 21 I, to The tension of the spring 211 is adjusted by a screw 212, access to which may be had through an opening 213 in the housing 191 of the pump. The relief passage 214 in turn is in open communication with the intake passage 226 leading to the cylinder 204. Thus, when hydraulic pressure is once built up in the pressure line 184 and is not needed by the servos, additional fluid supplied to the pump is simply recirculated through the outlet passage 201, ball valve 219, relief passage 214 and back into the cylinder 264 by way of the intake passage S. This is necessary because the gears 193 and 2133 are normally driven by the engine of the motorcycle so that they are in constant operation whenever the engine is running. Obviously, most of the time while the engine is running, there will be no need for actuation of the servos.

Referring to Figure ll of the drawing, the storage tank 189 comprises a shell of any suitable metallic material into which the exhaust conduit 18B opens. The tank 189 is provided with a suitable upwardly-opening vent 215 which opens therefrom at the upper end thereof. There is also provided a filler plug 216 for replenishing the fluid in the tank 189. Such plug is obviously located in an upper portion of the tank. The bottom of the tank includes a cylindrical strainer 211 of any suitable strainer material, which is secured axially of the tank by means of an arcuate plate 218 which is secured across an opening 219 in the bottom of the tank by any suitable fastening members 229. The supply conduit 19!) is con nected to the cylindrical strainer 211 axially thereof. Adjacent the strainer 211 in the bottom of the tank 189 there is provided a drain plug 221 for draining the tank.

The accumulator 181 is integral with the storage tank 189 and includes a concavo-convex wall 222 which closes the top of the storage tank 189. The convex side of the wall 222 extends into the storage tank 189 and is closed at the top by a iiexible diaphragm 225 which is secured across the top of the concave side of the wall 222 by any suitable fastening means 225. This structure provides a pressure chamber 223 which is substantially hemispherical in shape. Also secured across the top of the tank 18S is a domed shell 226 which is secured in place by the fastening means 225 aforesaid, and which comprises a substantially hemispherical air chamber 221 on the opposite side of the diaphragmy 22A. An air inlet 228 is formed in the top of the shell 226 and is controlled by a one-way air valve 229 of any suitable fcrm, and which is effective to admit air to the chamber 221, but prevents the escape of air therefrom. In operation, the pump 185 supplies hydraulic fluid to the accumulator by way of the conduit 186 which empties into the pressure chamber 223 at the bottom thereof. As hydraulic fluid lls the chamber 223, the diaphragm 224 is distended to the broken line position, Figure ll,

whereby to compress air in the air chamber 221. l

The resilience inherent in the compressed air in the chamber 221, plus the natural resiliency of the flexible diaphragm 224, serves to impose pressure upon the fluid in the pressure chamber 223, whereby, in the event that the pump is not operating, as when the engine is idle, there will be sufcient hydraulic fluid under pressure in the chamber 223 to operate both of the servos forat least one operation. As pressure drops in the chamber 223, the diaphragm 224 will tend to return to normal under pressure of air in the air chamber 221. Air under pressure is admitted to chamber 221 as needed Via the valve 22S. In normal operation, however, the accumulator 181 is not needed, and operating pressure for the servos is obtained in the usual manner from the pump 185. At the same time, by virtue of the connection of the accumulator to the pressure line 1M, of the pump, a constant pressure is maintained in the pressure tank 223 of the accumulator for use when needed.

To sum up the foregoing operation, when the gears are in neutral with the engine running, to engage a gear, the operator merely closes the desired selector switch to close a circuit to the clutch servo solenoid, whereby the same is operated to disengage the clutch. At the end of the declutching operation, the switch 89 is operated to close a circuit to one of the gear-shifting servo solenoids, whereby to drive the same in an appropriate direction to perform the selected gearshifting act. At the conclusion of the gear-shifting operation, the selected brush 63 of the slider 51B is centered on its insulated gap 53 in the junction box 41, whereby to open the circuit. Upon opening of the circuit, the appropriate gear-shifting servo solenoid is de-energized, whereby to shut off the flow of hydraulic fluid to cylinder 1122 and lock piston 143. Simultaneously, the clutch servo solenoid is de-energized, whereby to reverse the clutch servo slide valve and admit fluid to cylinder 131 to drive the piston 128 in a direction to engage the clutch.

Of course, the selected relay 12 or 8i! opens as the circuit breaks. In this connection, it is noted that one of the one way relays '12 or 80 is always open to prevent back flow of current to the end of the junction box opposite to that through which current is flowing, whereby to prevent simultaneous energization of both of the gear-shifting servo solenoids.

The tell-tale signal Q1 is actuated immediately before the clutch engages, and normally stays actuated until the clutch is disengaged. The clutch safety switch 1M is eective only to actuate the clutch servo to disengage and engage the clutch when the operator wishes to stop and leave the vehicle in gear. Actuation of this safety switch 1M from the go to the stop position closes a circuit to the clutch servo solenoid whereby the clutch is disengaged. As the clutch is disengaged, switch 8S is actuated as usual. However, no circuit is established to either of the gear-shifting servo solenoids, as no actuation of a selector switch has been made since the last gear-shifting act. Consequently, the appropriate slider brush is still centered on its insulating gap. Thus, no actuation of either slide valve for the gear-shifting servo results. When an operator wishes to start up, he merely reverses the clutch safety switch from the stop to the go position, whereby the circuit to the clutch servo solenoid is broken, the clutch servo slide Valve is reversed, and the clutch is reengaged.

While we have shown and described what is now thought to be the preferred embodiment of our invention, it is to be understood that the same is susceptible of other formsy and expressions. Consequently, We do not limit ourselves tothe precise structure shown and described hereinabove except as hereinafter claimed.

We claim:

l. In a change-speed device, the combination with a variable speed transmission including a plurality of shiftable gears, gear-shifting means, a driving shaft, a clutch operatively connecting said shaft to said transmission, and clutchactuating means for engaging and disengaging said clutch; of separate clutch and gear-shifting servos for separately actuating said gear-shitting and clutch-actuating means, electric control means for said servos including a plurality ol normally open circuits, a junction box, each circuit including a substantially identical slide rod, insulating means rigidly mounting said rods in said junction box in laterally-spaced parallel relation, a slider slidable on all of said rods within said junction box, a separate contact brush slidably engaging each rod and carried by said slider', means insulating said brushes from each other, a separate stationary contact bar slidably engaged by eachv brush, said Contact bars being xed in said junction box substantially parallel to said rods and being spaced and insulated therefrom, a gap in each bar, said gap of each bar being staggered longitudinally relative to every other gap, bus bars connecting lie opposite ends of said Contact bars, Selector means operative upon actuation to establish a selected circuit through a slide rod, a brush, a contact bar and a bus bar to said control means for said clutch servo whereby to actuate the latter to disengage said clutch, means operative upon disengagement of said clutch to establish said circuit to said control means for said gear-shifting servo whereby to actuate the latter to perform a selected gear-shifting operation, means operatively connecting said gear-shifting servo to said slider to slide the same and the selected brush toward said gap or said selected contact bar, said gap being positioned to open said circuit at the completion of said shifting operation, and means operative upon the opening of said circuit to lock said gear-shifting servo and reengage said clutch.

2. In a change-speed device, the combination with a variable speed transmission including a plurality of shiftable gears, gear-shifting means, a driving shaft, a clutch operatively connecting said shaft to said transmission, and clutch-actuating means for engaging and disengaging said clutch; of separate clutch and gear-shifting servos for separately actuating said gear-shifting and clutch-actuating means, electric control means for said servos including a plurality of normally open circuits, a junction box, said box including a plurality of pairs of spaced and insulated stationary contacts, there being a pair of such contacts for each circuit, each circuit being operatively connected to one contact of each pair, a movable Contact bridging each pair of contacts, one stationary contact of each pair being formed with a gap therein, said gaps being staggered relative to each other, selector means operative upon actuation to establish a selected circuit across its related pair of stationarx contacts over the related movable contact to said control means for said clutch servo whereby to actuate the latter to disengage said clutch, means operative upon disengagement of said clutch to establish said selected circuit to said control means for said gear-shifting servo whereby to actuate the latter to perform a selected gearshiiting operation, means operatively connecting said gear-shifting servo to said movable contact and operative to move the same toward gap during said operation and to position said movable contact over said gap at the completion of said operation whereby to open said selected circuit, and means operative upon the opening of said circuit to lock said gear-shifting servo rind simultaneously actuate said clutch servo to reengage said clutch.

3. In a change-speed device, the combination with a v riable speed transmission including a plurality of shiitable gears, gear-shifting means, a driving shaft, a clutch operatively connecting said shaft to said transmission, and clutchactuating means for engaging and disengaging said clutch; of separate clutch and gear-shifting servos for separately actuating said gear-shifting and clutch-actuating means, electric control means for said servos including a plurality of normally open circuits, a junction box, said box including a plurality of spaced stationary contacts, a plurality of movable contacts, there being a movable contact in operative contact with each stationary contact, means operatively connecting each circuit to one of said movable contacts, each of said stationary contacts being formed 'with a gap therein, said gaps being staggered, a single means mounting all of said movable contacts for simultaneous movement along said stationary contacts, selector means operative upon actuation to establish a selected circuit across a selected pair of movable and stationary contacts to said control means for said clutch servo whereby to actuate the latter to disengage said clutch, means operative upon disengagement of said clutch to establish said selected circuit to said control means for said gear-shifting servo whereby to actuate the latter to perform a selected gear-shifting operation, means operatively connecting said gear-shifting servo to said mounting means for said movable contact and operative to move the same toward said gap oi said selected stationary contact during said operation and to position said selected movable Contact over said gap at the completion of said operation whereby to open said selected circuit, and means operative upon the opening of said circuit to lock said gear-shifting servo and sini-ultaneously actuate said clutch servo to re-'engage said clutch.

4. In a change-speed device, the combination with a variable spcedtransmission including a plurality of shiftable gears, gear-shifting means, a driving shaft, a clutch operatively connecting said shaft to said transmission, and clutchactuating means for engaging and disengr said clutch; of separate clutch and gear-shit ng servos for separately actuating said gear-shifting and clutch-actuating means, electric control means for said servos including a plrxality of normally open circuits, a junction box, said including a plurality of spaced stationary contacts, a plurality of movable contacts, there being a movable contact in operative contact with each stationary contact, means operatively connecting each circuit to one of said movable contacts, each of said stationary contacts being formed with a gap therein, said gaps being staggered, a single means mounting all of said movable contacts for simultaneous movement along said stationary contacts, selector means operative upon actuation to establish a selected circuit across a selected pair of movable and stationary contacts to said control means for said clutch servo whereby to actuate the latter to disengage said clutch, means operative upon disengagement of said clutch to establish said selected circuit to said control means for said gear-shifting servo whereby to actuate the latter to perform a selected gear-shifting operation, means operatively connecting said gear-shifting servo to said mounting means for said movable contact and operative to move the same toward said gap or said selected stationary contact during said operation and to position said selected movable contacts over said gap at the completion of said operation whereby to open said selected circuit, said clutch and gear-shifting servos comprising a separate hydraulic cylinder, piston and valve chest units for each, said control means for said clutch servo comprising a double-action slide valve and a solenoid operatively connected thereto to open said valve upon energization and move said piston and disengage said clutch and operative upon de-energization to reverse said valve and reverse the movement of its piston whereby to re-engage said clutch, said gear-shifting servo comprising a pair of normally closed singleacticn slide valves in the related valve chest, each operative to drive said piston in an opposite direction, a solenoid operatively connected to each of said last named slide valves and operative upon energization to open the same, a lead connecting portions of each stationary contact on one side of said gap to said rst solenoid and to one of said last-named solenoids, a separate lead connecting portions of leach stationary contact on the opposite sides of said gaps to said nrst solenoid and to the other of said last-named solenoids, a one-way relay interposed in each ci said last-named leads whereby but one of said last-named solenoids will be energized at a time, and means delaying actuation of said last-named solenoids until said clutch is disengaged.

In a change-speed device, the combination with a variable speed transmission including shiftable gears, a driving shaftka clutch operatively connecting said shait to said transmission, and gear-shifting means; of a hydraulicallypowered clutch-actuating servo, comprising a unit including a valve chest, a cylinder, a piston in said cylinder and a piston rod adapted to be operatively connected to said clutch for disengaging the same upon movement oi said piston rod in one direction with said piston and for engaging said clutch upon movement of said piston rod in the opposite direction, said valve chest including two laterally-aligned pairs of conduits, one conduit o each pair being an inlet conduit for the passage o hydraulic fluid under pressure to an opposite end of said cylinder, the other conduit of each pair being an exhaust conduit for the passage of exhausted hydraulic uid from opposite ends of said cylinder, a double-action slide valve, means slidably mounting said valve in said chest across all of said conduits, said valve being formed with a pair of spaced ports for each pair of conduits, said ports being arranged to cause said cylinder to be driven in a clutch-disengaging direction with said valve in one position and to be driven in a clutch-engaging direction with said valve in an opposite position, means biasingv 18 gization to move said valve to said rst position, and means for energizing said solenoid.

6. The structure of claim 5, and means for regulating the now of iluid in said inlet conduits whereby to regulate the speed of operation of said piston.

'7. In a change-speed device, the combination with a variable speed transmission including shitabie gears, a driving shaft, a clutch operatively connecting said shait to said transmission, and means ior actuating said clutch; of a hydraulically-pcwered gear-shifting servo, comprisa unit including a valve chest, a cylinder, a piston in cylinder, a pair of piston rods fixed to said piston extending outwardly of said cylinder in opposite directions, said valve chest including two pairs of spaced conduits, the conduits oi each pair being inlet and exhaust conduits for opposite ends of said cylinder whereby each pair of conduits when open is operative to drive said piston in an opposite direction, a pair of single-action slide valves, means slidably mounting each valve in said chest across a different pair of conduits, each valve being adapted in one position to close its pair of inlet and exhaust conduits and in an' opposite position to open its pair oi inlet and exhaust conduits, means biasing both of said valves to said first positions, separate solenoid means operatively connected to each valve and each operative upon energization to move a valve to the second position, one of said piston rods being adapted to connected to gear-shifting means, means associated with said other piston rod for selectively energizing one of said solenoids whereby to actuate said piston in a selected direction to perform a selected gear-shifting operation, and means automatically rie-energizing said selected solenoid upon completion of said selected operation.

8. The structure of claim 7, and means for regulating the flow of iluid in said inlet conduits whereby to regulate the speed of operation of said piston.

9. In a change-speed device, the combination with a variable speed transmission including shiftable gears, a driving shaft, a clutch operatively connecting said shaft to said transmission, and means for actuating said clutch; of a hydraulically-powered gear-shifting servo, comprising a unit including a valve chest, a cylinder, a piston in said cylinder, means operatively connected to said piston for performing selected gear-shifting operations upon movement of said piston in either direction, a pair of normally closed single-action slide valves in said valve chest, each of said valves being operative when opened to drive said piston in an opposite direction, a solenoid operatively connected to each valve and operative upon energiaation to open the same, means movable with said piston and operative to energize a selected solenoid whereby to actuate said piston to perform a selected gear-shifting operation, and means automatically cie-energizing said selected solenoid upon compietion ci said selected operation.

l0. In a change-speed device, the combination with a variable speed transmissionincluding shiftable gears, a driving shaft, a clutch operatively connecting said shaft to said transmission, and gear-shifting means; of a hydraulically-powered clutch-actuating servo, comprising a unit including a valve chest, a cylinder, a piston in said cylinder, and means operatively connecting said piston and clutch whereby actuation of said piston in one direction is effective to disengage said clutch and in the other direction is electiye to `engage said clutch, a double-action slide valve in said chest operative in opposite positions to drive said,` piston in opposite directions, means biasing said valve to a clutch-engaging position. a solenoid operatively connected to said valve operativeupon energization to move said valve to a clutch-disengaging position, and means for energizing said solenoid. ll. In a change-speed device, the combination with a variable speed transmission including shiftable gears, a driving shaft and a clutch operatively connecting said shaft to said transmission, of a hydraulically powered gear shifting servo, comprising a unit including a valve chest, a cylinder, a piston in said cylinder, means operatively connected to said piston for performing selected gear shifting operations upon movement of said piston in either direction, a pair of normally closed single action slide valves in said valve chest, each of said valves being operative when open toY drive said piston in a different direction, a solenoid operatively connected to each valve and operative upon energization to open the same, means movable with said piston and operative to energize a selected solenoid whereby to actuate said piston to perform a selected gear shifting operation, means automatically deenergizihg said selected solenoid upon completion of said selected operation, a hydraulically powered clutch actuating servo, comprising a unit including a valve chest, a cylinder, a piston in said last named cylinder and means operatively connecting said last named piston and clutch whereby actuation of said last named piston in one direction is eiective to disengage said clutch and in the other direction is eiective to engage said clutch, a double action slide valve in said last named valve chest operative to control through a pressure to one side or the other of said last named piston to thereby control its movement in one direction or the other, means biasing said double action slide valve to a clutch engaging position, a solenoid operatively connected to said last named valve, said last named solenoid being operative upon energization to move said double action slide valve to a clutch disengaging position, and means for energizing said last named solenoid.

i2. a change-speed device, the combination with a variable speed transmission including a plurality of shi-ftable gears, Ygear-shifting means, a driving shaft, a clutch operatively connecting said 'shaft to said transmission, and clutch-actuating means for engaging and disengaging said clutch;V of separate clutch and gear-shifting servos for separately actuating said gear-shifting and clutch-actuating means, electric control means Yfor said servos including a plurality of normally open circuits, a junction box, said box including a plurality of spaced stationary contacts, a plurality of vmovable contacts, there being a movable contact in operative contact with each stationary contact, means operatively connecting each circuit to one of said movable contacts, each of said stationary contacts being 4formed with a gap therein, said gaps being staggered, a single means mounting all of said movable contacts for simultaneous movement along said stationary contacts, selector means operative upon actuation to establish a selected circuit across a selected pair of movable and stationary contacts to said control means for said clutch servo whereby to actuate the latter to disengage said clutch, means operative upon disengagement of said 'clutch t establish said selected circuit to said control means for said gear-shifting servo whereby to actuate the latter to perform a selected gear-shifting operation, means operatively connecting said Agear-shifting lservo to said mounting means for said movable 'contact and operative to move the same toward said gap of said selected stationary contact during said operation and to position said selected movable contact over said gap at the completion of said operation whereby to open said s'elected circuit, and means operative upon the opening of said circuit to actuate said clutch 4servo to reengage said clutch. n

1-3. In a change-speed device, the combination with a variable speed transmission including a plurality of shiftabl'e gears, gear-shifting means, a driving shaft, 'a clutch operatively connecting said shaft to said transmission, and clutch-actuating means fo'r engaging and disengag-ing said clutch; of separate clutch and gear-shifting servos for separately Vactuating said ygear-shifting and clutch-actuating means, electric control means for said servos including a plurality of normally open circuits, a junction box, said box including a plurality of separate circuit closers, there being 'a separate normally closed circuit closer for Aeach 'of said circuits, a single actuating means ior selectively opening each circuit closer, selector means operative upon actuation to establish a selected circuit through the related circuit closer to said control means for 'said clutch servo whereby to actuate the latter to disengage said clutch, means 'operative upon disengagement of said clutch to establish said selected circuit to said control means for said gear-sluiting servo whereby to actuate the latter to perform a selected 'gear-shifting operation, means operatively connecting said gear-sluiting servo to said actu'- ating means for said selected lcircuit closer and operative to open the 's'ame Vand said selected circuit `at the completion of said operation, and means operative upon the opening 'of said circuit to lock said gear-"shifting servo and simultaneously actuate said clutch servo to reengage said clutch.

14. In a change-speed device, the combination with a variable speed transmission including a plurality of shiltalole gears, gear-'shifting means, a driving shaft, a clutch operatively connecting said shaft to said transmission, and clutch-actuating means for. 'engaging' and disengaging said clutch; of separate clutch and gear-shifting servos io'r separately actuating said gear-shifting and clutchactuating means, electric control means for said 'servos including a plurality oi normally open circuits, a junction box, said box including a plurality of separate circuit closers, there being a separate normally closed circuit closer for each 'of said circuits, a single actuating means for selectively vvopening each circuit closer, selector means operative upon actuation to establish a selected circuit through the related circuit c'loser to said control -means for said clutch servo whereby toactuate the latter to disengage lsaid clutch, means operative upon disengagement of said clutch to establish said selected circuit to said control means lfor said rgear-shifting servo whereby to actuate the latter to per-form a selected gear-shifting operation, means operatively connecting 'said gear-shifting servo to said actuating means for vsaid selected circuit Icloser and operative to open the same and said selected circuit at the A'completion of said operation, and means operative upon the opening of said circuit to actuate said clutch servo to reengage said Number Name Date clutch. 1,544,909 Josephs et al July '7, 1925 LEONARD T. WOMACK. 1,665,909 Craig Apr. 10, 1928 JEWEL JACKSON WOMACK- 2,035,678 Swift Mar. 31, 1936 5 2,073,264 McDonald Mar. 9, 1937 REFERENCES CITED 2,235,943 Mylius Mar. 5, 1941 The following references are of record in the 2,244,092 Wheflel June 3, 1941 me of this patent: Iceslmg 114391- ameron ec. UNITED STATES PATENTS m 2,397,883 Peterson et a1 Apr. 2, 194s Number Name Date 2,420,890 MacDuff May 2o, 1947 925,270 Beemer June 15, 1909 

